Multirotor aircraft with a thrust producing unit that comprises an aerodynamically optimized shrouding

Abstract

A multirotor aircraft with an airframe that extends in a longitudinal direction, and with at least one thrust producing unit for producing thrust in a predetermined thrust direction, wherein the at least one thrust producing unit comprises a shrouding that is associated with at least one rotor assembly comprising at least one electrical engine, wherein the shrouding defines a cylindrical air duct that is axially delimited by an air inlet region and an air outlet region, and wherein a carrier beam is at least mounted at a leading edge region of the cylindrical air duct to the shrouding such that the carrier beam is arranged inside of the cylindrical air duct and oriented at least essentially in parallel to the longitudinal direction, the at least one electrical engine being mounted to the carrier beam.

What is claimed is: 
     
       1. A multirotor aircraft with an airframe that extends in a longitudinal direction, and with at least one thrust producing unit for producing thrust in a predetermined thrust direction, wherein the at least one thrust producing unit comprises a shrouding that is associated with at least one rotor assembly comprising at least one electrical engine, wherein the shrouding defines a cylindrical air duct that is axially delimited by an air inlet region and an air outlet region, wherein a carrier beam is at least mounted at a leading edge region of the cylindrical air duct to the shrouding such that the carrier beam is arranged inside of the cylindrical air duct and oriented at least essentially in parallel to the longitudinal direction, wherein the shrouding comprises a forward beam and an aft beam which both connect the carrier beam to the airframe, the forward beam and the aft beam being arranged outside of the cylindrical air duct, wherein the forward beam comprises a forward flange, and wherein the aft beam comprises an aft flange, the forward flange and the aft flange being attached to the airframe, and wherein the at least one electrical engine is mounted to the carrier beam. 
     
     
       2. The multirotor aircraft of  claim 1 ,
 wherein the carrier beam is arranged eccentrically inside of the cylindrical air duct and at least essentially coplanar to a cross section of the cylindrical air duct. 
 
     
     
       3. The multirotor aircraft of  claim 1 ,
 wherein the carrier beam is a cantilever. 
 
     
     
       4. The multirotor aircraft of  claim 1 ,
 wherein the carrier beam is further mounted at a trailing edge region of the cylindrical air duct to the shrouding. 
 
     
     
       5. The multirotor aircraft of  claim 4 ,
 wherein the carrier beam is bar-shaped and extends from the leading edge region to the trailing edge region. 
 
     
     
       6. The multirotor aircraft of  claim 1 ,
 wherein the forward beam and the forward flange are integrally formed, wherein the aft beam and the aft flange are integrally formed, and/or wherein the forward flange and the aft flange are integrally formed. 
 
     
     
       7. The multirotor aircraft of  claim 1 ,
 wherein the cylindrical air duct is provided in closed perimeter configuration or in opened perimeter configuration, the shrouding being at least partly cut-off in the opened perimeter configuration at a trailing edge region of the cylindrical air duct over a predetermined opening angle. 
 
     
     
       8. The multirotor aircraft of  claim 1 ,
 wherein the shrouding is provided with an additional lifting surface at the leading edge region of the cylindrical air duct. 
 
     
     
       9. The multirotor aircraft of  claim 1 ,
 wherein the at least one electrical engine is eccentrically mounted to the carrier beam. 
 
     
     
       10. The multirotor aircraft of  claim 1 ,
 wherein the air inlet region exhibits in circumferential direction of the cylindrical air duct an undulated geometry, wherein the cylindrical air duct comprises in circumferential direction the leading edge region and a diametrically opposed trailing edge region, a board side lateral region and a diametrically opposed star board side lateral region, wherein the board side lateral region and the star board side lateral region are respectively arranged in the circumferential direction of the cylindrical air duct between the leading edge region and the trailing edge region, and wherein a height at the leading edge region is smaller than a height at the board side lateral region and/or the star board side lateral region. 
 
     
     
       11. The multirotor aircraft of  claim 10 ,
 wherein the cylindrical air duct exhibits a height defined between the air outlet region and the air inlet region in axial direction of the cylindrical air duct that varies in circumferential direction of the cylindrical air duct, wherein the height that varies in the circumferential direction of the cylindrical air duct defines the undulated geometry of the air inlet region. 
 
     
     
       12. The multirotor aircraft of  claim 10 ,
 wherein the height at the trailing edge region is smaller than a height at the board side lateral region and/or the star board side lateral region. 
 
     
     
       13. The multirotor aircraft of  claim 10 ,
 wherein the height at the trailing edge region is smaller than the height at the leading edge region. 
 
     
     
       14. A multirotor aircraft comprising:
 an airframe extending in a longitudinal direction; and 
 at least one thrust producing unit for producing thrust in a predetermined thrust direction; 
 the at least one thrust producing unit comprising:
 at least one rotor assembly comprising at least one electrical engine; 
 a shrouding associated with the at least one rotor assembly, the shrouding comprising a wall defining a cylindrical air duct axially delimited by an air inlet region and an air outlet region, 
 a carrier beam mounted at a leading edge region of the cylindrical air duct to the shrouding such that the carrier beam is arranged inside of the cylindrical air duct and oriented essentially parallel to the longitudinal direction, and 
 a forward beam and an aft beam, the forward and aft beams connecting the carrier beam to the airframe, the forward beam and the aft beam arranged outside of the cylindrical air duct, wherein the forward beam comprises a forward flange, and wherein the aft beam comprises an aft flange, the forward flange and the aft flange being attached to the airframe, 
 
 wherein the at least one electrical engine is mounted to the carrier beam. 
 
     
     
       15. The multirotor aircraft of  claim 14 ,
 wherein the carrier beam is arranged eccentrically inside of the cylindrical air duct and at least essentially coplanar to a cross section of the cylindrical air duct. 
 
     
     
       16. The multirotor aircraft of  claim 14 ,
 wherein the at least one electrical engine is eccentrically mounted to the carrier beam. 
 
     
     
       17. The multirotor aircraft of  claim 14 ,
 wherein the air inlet region exhibits in circumferential direction of the cylindrical air duct an undulated geometry. 
 
     
     
       18. The multirotor aircraft of  claim 17 ,
 wherein the cylindrical air duct exhibits a height defined between the air outlet region and the air inlet region in axial direction of the cylindrical air duct that varies in circumferential direction of the cylindrical air duct, wherein the height that varies in the circumferential direction of the cylindrical air duct defines the undulated geometry of the air inlet region. 
 
     
     
       19. The multirotor aircraft of  claim 14 ,
 wherein the air inlet region exhibits in circumferential direction of the cylindrical air duct an undulated geometry, wherein the cylindrical air duct comprises in circumferential direction the leading edge region and a diametrically opposed trailing edge region, a board side lateral region and a diametrically opposed star board side lateral region, wherein the board side lateral region and the star board side lateral region are respectively arranged in the circumferential direction of the cylindrical air duct between the leading edge region and the trailing edge region, and wherein a height at the leading edge region is smaller than a height at the leading edge region. 
 
     
     
       20. The multirotor aircraft of  claim 14 ,
 wherein the carrier beam is bar-shaped and extends from the leading edge region to the trailing edge region.